The present invention relates to a method of and arrangement for winding capacitors.
It has been proposed in the art to wind a capacitor by means of a spindle forming an integral part of the machine and to thereafter remove the obtained article from the spindle which article includes a central through-going channel with open axial ends.
It is therefore necessary to obturate the open ends of the channel before subsequent metallization of the article. This operation is delicate and frequently even imperfect, because the particles of the metal can penetrate into the capacitor and short-circuit the same.
Furthermore, the central turns of the winding, that is the turns first wound are not supported and the temperature variations may cause changes of their positions and thereby may also cause changes of the capacitance of the capacitor.
It also is appropriate to mention that sliding of the article relative to the spindle can damage the initial turns of the metallized films.
In order to overcome these disadvantages, another method has been proposed including winding of the capacitor onto a mandrel made of an insulating material, which mandrel remains inside of the winding.
This method requires fixation of the films on the mandrel which is to be rotated. This fixation is performed by glueing of an initial portion of the film to the mandrel.
Such an operation is delicate and therefore slow.
In addition thereto, this operation is connected with application of sometimes instable material which could be harmful for the capacitor.